Fox Foto Friday - Injured Island Fox Back on Her Feet

This young female island fox was discovered during capturing of island foxes for counting and health checks with a broken rear leg. Her story is one of multiple agencies, institutions, and a community of people working together to help her survive.

Friends of the Island Fox and donors like you helped raise the $1,900 to pay for her specialized orthopedic surgery. Following her orthopedic evaluation on March 15, Julie Barnes, V.P. of Animal Care and Health at the Santa Barbara Zoo, reported that "the fracture is healing really well and no longer needs bandaging." 

March 28th and she is standing solidly on all four legs!

All island foxes are under the jurisdiction of the California Dept. of Fish & Wildlife (CDFW). Removing an individual from its island habitat is a major decision because once an island fox comes off of its island of origin, it can not be returned. Because island foxes evolved in isolation on the Channel Islands, they are very susceptible to diseases from the mainland. Canine distemper virus is lethal to them and nearly caused extinction on Catalina Island in 1998. Today, a minimum of 100 island foxes are vaccinated against distemper on each island annually. (Help FIF vaccinate foxes)

To protect the wild population, the injured female island fox can not return to San Nicholas Island. The CDFW has approved The Living Desert Zoo and Gardens in Palm Springs as her new home. The Living Desert is an American Zoo Association accredited zoo and has cared for other island foxes in the past. She will be moving to her new home March 30th.

Currently, there are six (Update 5/23/24 - five) island foxes living in zoos on the mainland. The CDFW requires that each facility only have males or females, since no island foxes can be bred on the mainland for release on the islands.

If you can't travel to the Channel Islands, you can see island foxes at:

The Santa Barbara Zoo

Brothers, Lewis and Clark, were left abandoned pups after their mother was hit by a car on San Clemente Island. The Santa Barbara Zoo leads the zoo community's efforts toward island foxes and hosts the annual Island Fox Conservation Working Group Meeting. (Update: Clark passed away at 8 years old on May 17, 2024, Lewis remains healthy and on exhibit.)

California Living Museum, Bakersfield

Two sisters, from San Clemente Island, were abandoned by their parents as pups during a drought year. They were in an enclosure with a female gray fox. The only place where you can see these two species side-by-side. (Update: one sister passed away in 2023.)

The San Diego Zoo Safari Park
Is home to Sage, a female island fox from Catalina Island, who was separated from her parents by people as a pup, resulting in chronic health issues. She was unable to be released back into the wild and requires regular veterinary care. 

The little San Nicolas Island fox joins her five cousins as ambassadors for their wild relatives. They tell a story of how human actions can be detrimental or positive for island foxes.

The San Nicolas Island fox has a second chance because people like you came to her aid.

FIF Research Grant Application 2024

Friends of the Island Fox is currently taking applications 

through June 30 for the 

FIF 2024 Research Grant

Download Application

From the complex relationship between island foxes and island spotted skunks, to diet, microbiome impacts on health, and changing territory sizes, research projects are revealing the complexities of the Channel Island ecosystem and the role of island foxes in island ecology.

In 2024, Friends of the Island Fox is offering up to $7,000 in support to research projects benefiting greater understanding of the island fox and the Channel Island ecosystem.

 

Last year's grant recipients are using wildlife cameras to quantify island spotted skunk populations and investigating the impact of individual island fox behavior on the island ecosystem.

It's Science, for Fox Sake! And we encourage all applicants to apply.

 

2023 grant recipient, D. Thomaier

Past Research Grant Recipients and Projects

Grant Recipients are asked to provide public updates on their work - "Date with a Fox" programs, hear from the researchers

Published science on island foxes and island spotted skunks

 

 

Your Donations Help Fund this Important Science!

FIF 2023 Research Grant to Investigate Individual Island Fox Impact

FIF awarded a second Research Grant in 2023 to Juliann Schamel, NPS biologist and graduate student in Ecology and Conservation at University of Aberdeen, Scotland...

Juliann Schamel in the field with island fox

 

and Dr. Alexandria DeCandia, biology professor at Georgetown University...

Dr. Alexandria DeCandia

 

for their project: From Microbes to Habitats: How Individual Fox Foraging Behavior Cascades Through an Ecosystem.

Schamel and De Candia are combining their respective work in stable isotope diet analysis and microbiome research to investigate the specific interconnections between 15 male island foxes and the island ecosystem. The team says, "Recent research has revealed that the island fox displays a high level of individual specialization, from their diet, to activity patterns, to the germination rate of scat-dispersed native seeds." This work builds on stable isotope diet analysis that Schamel presented at the Channel Island Symposium that demonstrated that diet specialization is occurring on Santa Rosa Island. 

GPS radio collar deployed on Santa Rosa Island

The 15 island foxes to be studied were part of a territory range investigation monitoring island fox movement with GPS radio collars by FIF 2021 Research Grant recipient Katie Elder. The final collection of data occurred in December 2023 when the island foxes were recaptured and their GPS collars removed.

Combining specific daily movement data (over the course of a year) with stable isotope diet data from individual whisker samples and microbiome swabs of gut microfloral offers a unique window into the lives of these individual island foxes. 

Microbiome sample swabs

 

It's easy to assume that island foxes, as a species, have a specifically defined relationship with plants and animals in the island ecosystem. However, Schamel's island fox dietary data has revealed a great deal of individualism in dietary choice, especially when resources are abundant. Some island foxes are eating beach foods, some are fruit specialists, others prey predominantly on deer mice.

Island fox whisker sample being collected

 

This investigation will try to reveal "a more holistic understanding of island foxes," DeCandia says. "[H]ost-associated microbes are critical to ... digestion and immunity,... By linking gut microbial communities with individual diet, movement, and activity patterns, we can begin to untangle the eco-evolutionary factors shaping these island hosts, their microbes, and the ecosystem in which they live."

Comparing microbiome of island fox and island spotted skunk, A. DeCandia

 

Friends of the Island Fox is proud to invest in this cutting-edge, multidisciplinary scientific investigation that brings together academic and governmental organizations and investigators. Whisker samples will be processed and analyzed by Julianne Schamel and Seth Newsome at the Center for Stable Isotopes at the University of New Mexico. DNA from microbiome swabs will be extracted by Alexandria DeCandia at the Center for Conservation Genomics at the Smithsonian's National Zoo and Conservation Biology Institute. Undergraduate researchers at Georgetown University, University of New Mexico, and California State University Channel Islands will actively participate in sample collection, laboratory preparation, data analysis and interpretation, and co-authorship of findings. 

Your donations help grow scientific knowledge and the next generation of scientists! 

Applications for FIF's 2024 Research Grant 

will be available March 22

Stable Isotopes Document Decade of Dietary Change in Island Foxes

Juliann Schamel has been researching island fox diet using stable isotopes in whisker samples since 2018. Friends of the Island Fox has supported the processing of whisker samples through several Research Grants. In November of 2023, Schamel presented the following poster of her latest work at the California Islands Symposium.

Using Stable Isotopes to Assess a Decade of Dietary Resource Use in Two Sympatric Island Endemics: The Island Fox and the Island Spotted Skunk (link to complete poster)

Island foxes and island spotted skunks live together on two islands, Santa Rosa and Santa Cruz. When island fox numbers crashed due to predation by golden eagles, island spotted skunk numbers appeared to increase dramatically. In 2011, on Santa Rosa Island, there were still fewer than 90 island foxes in the wild. During annual health checks, whisker samples were collected from both island foxes and island spotted skunks in a northern area of the island and stored for later analysis of what food resources each species was using.

In 2011, island spotted skunks out numbered island foxes in the wild. Stable isotope analysis shows that the skunks and foxes were using different resources. 

J. Schamel, 2023 poster

 

Carbon and nitrogen isotopes travel up the food chain leaving a specific isotope signature for plant and animal resources. Literally, you are what you eat and isotopes from a mammal's diet are laid down chronologically in hair or fur. A single island fox whisker can provide 5–6 months of weekly diet data. On the graph above, native terrestrial plant foods, like manzanita berries, are high in Carbon and low in Nitrogen. A deer mouse is the accumulation of its own, mostly plant diet; it has a mid-range Carbon and Nitrogen signature. In the graph above, the blue data points represent island fox diet and the orange data points represent island spotted skunk diet. 

In 2011, when island fox numbers in the wild were low, their diet tended to be higher on the food chain or trophic level: deer mice, birds and reptiles. The data suggested separate diet niches for island foxes and island spotted skunks. The skunks were eating primarily, lower level prey, like insects, and some plant foods.

J. Schamel, 2023 poster

In 2014, continuing drought influenced wildlife survival; island fox and island spotted skunks were nearly even in number on Santa Rosa Island. Island foxes expanded their diet, including marine resources, and island spotted skunks preyed more on deer mice and higher level prey. The two predators began competing for resources.

J. Schamel, 2023 poster

By 2018, the island fox population had recovered, but island spotted skunks appeared to decline in number. (Counting island spotted skunks) As island fox density increased across the island, they dramatically broadened their diet–from native fruit through a range of prey species. The spotted skunks maintained a more narrow diet, but they were now in constant competition with island foxes. What will this mean for the two species?

Schamel's work also revealed that individual island foxes are becoming specialized in their diet.

J. Schamel, 2023 poster

 

In the graphic above, each circle of data points represents an individual island fox and its diet. Some individuals appear to be specializing in fruit and insects, while others are eating predominately terrestrial prey. How is island fox diet continuing to change?

Save the date of April 30th at 6:30 pm PT 

Juliann Schamel will talk about her work on 

FIF's "Date with a Fox" webinar

sign-up for FIF's e-newsletter to receive an invitation

Measuring out a whisker sample

Whisker samples continue to be collected for both species. 

designed by island biologist, Stacy Baker

When you purchase an island spotted skunk pin, 

you send a sample of island spotted skunk whisker 

to the mass spectrometer to reveal stable isotopes.